Perception of hypertension and adherence to hypertension treatment among patients attending a hospital in western Iran: A cross‐sectional study

Abstract Background and Aims Hypertension is the third leading cause of death in the world and is estimated to be increased by about 60% by 2025. Beliefs about hypertension can predict patient adherence to hypertension treatment. This study aims to investigate the perceptions of hypertension and adherence to hypertension treatment among patients in Khorramabad, Iran. Methods This is a descriptive/analytical study with a cross‐sectional design. Participants were 265 patients with a history of hypertension referred to a hospital in Khorramabad, Lorestan Province in western Iran in 2020, who were selected using a convenience sampling method. A demographic form, the brief illness perception questionnaire‐revised (BIPQ‐R), and Morisky medication adherence scale (MMAS‐8) were used for collecting data. The collected data were analyzed in SPSS v.22 software using descriptive statistics, Pearson's correlation test, independent t‐test, one‐way ANOVA, and regression analysis. Results The mean scores of BIPQ‐R and MMAS‐8 were 49.05 ± 15.45 (out of 80) and 3.69 ± 1.62 (out of 8), respectively. There was a significant relationship between the mean scores of MMAS‐8 and BIPQ‐R in total (p < 0.001). Perceptions of illness consequences (B = 4.59, p = 0.005), personal control (B = 0.190, p = 0.047), and symptoms (B = 1.77, p = 0.005) could significantly predict treatment adherence of patients. In illness perception, there were significant differences among patients with different places of residence (p = 0.032), educational levels (p = 0.001), and employment status (p = 0.010). In treatment adherence, there were significant differences among patients with different places of residence (p = 0.042) and educational levels (p = 0.045). Conclusion Treatment adherence of hypertensive patients in western Iran is at a low level, while their perception of hypertension is at a moderate level. Clinical physicians are recommended to pay attention to the perception of illness in these patients (especially unemployed and less educated patients living in rural areas) to improve their adherence to treatment and blood pressure control.


| INTRODUCTION
Nowadays, high blood pressure or hypertension has become a growing problem. It is the most common cardiovascular disease. 1 It is the third leading cause of death in the world and is expected to cause 7.5 million deaths, accounting for about 12.8% of the total deaths per year. 2 About two-third of the population with hypertension globally live in low-and middle-income countries. 3 Studies have shown that the prevalence of hypertension in Iran is 25%. 4,5 By 2025, the number of people with hypertension is estimated to increase by about 60%, reaching 1.5 billion. 6 Therefore, to improve prognosis, early detection and treatment of hypertension are necessary. Globally, almost 31% of the adult population is affected by hypertension, among which only 36.9% go under treatment and 13.8% having can control their hypertension. 7 Treatment of hypertension and control of blood pressure can decrease cardiovascular events, morbidity, and mortality in both men and women. 8 Pharmacological and nonpharmacological methods are used in the treatment of hypertension. The main nonpharmacological measures are lifestyle modifications such as dietary regime, exercise, avoiding stress, or reducing alcohol consumption. 9,10 Adherence to treatment and medication is important to control high blood pressure. Low adherence to treatment is a major barrier to blood pressure reduction and control. 11 Lack of or poor treatment adherence increases cardiovascular morbidity and mortality. [12][13][14] According to the World Health Organization, treatment adherence is "the extent to which a person's behavior-taking medication, following a diet, and/or executing lifestyle changes-corresponds with the agreed recommendations from a healthcare provider." 15 Beliefs about specific medications and perception of illness are predictive of patient adherence to antihypertensive treatment. 16 Patients may not continue with treatment if they perceive it poorly. 17 Therefore, having knowledge of patient's perceptions are necessary for improving their adherence to treatment. Negative perceptions of illness are associated with more delay in recovery process and an increase in healthcare use; these perceptions can be modified by providing appropriate education. 18 Few studies have been conducted to assess both treatment adherence and perception of illness in hypertensive patients. showed that the patients perceived their hypertension as a chronically severe but stable disease and were sure about the efficacy of medical treatments and were able to control their disease. They recommended that clinical physicians should pay attention to patients' illness perceptions, including their negative emotional responses and symptoms to improve their adherence to medication. 19  stated that they did not take drugs because they forgot it. 23 Shakya et al. assessed illness perception and treatment adherence among hypertensive patients referred to a tertiary hospital in Nepal in 2020. Most of them perceived hypertension as a highly threatening illness and as a chronic disease, and had a high level of personal and treatment control. They found a significant positive relationship between the perception of illness and adherence to treatment. 18 Otenyo and Kereri investigated the influence of illness perception on adherence to medication in patients with hypertension admitted to a hospital in Kenya in 2021. They found that 33.3% of the patients had a high adherence level. 24  According to their findings, 63% of patients perceived that hypertension is not curable. Furthermore, 94% missed their follow-up, despite that their physician asked them for follow-up. 25 Treatment adherence is essential for optimal blood pressure control, and understanding patients' perceptions of illness are essential for improving treatment adherence. In this regard, and considering that no study was found on surveying both hypertension treatment adherence and perception of hypertension in western Iran, the current study aims to investigate hypertension treatment adherence and perception of hypertension in patients referred to a teaching hospital in western Iran. We also evaluated the association between their hypertension treatment adherence and perception of hypertension. The MMAS-8 is a structured self-report measure of medicationtaking behavior developed by Morisky et al. 28 This measure was designed to facilitate the recognition of barriers to and behaviors associated with adherence to chronic medications. The scale provides information on behaviors related to medication use that may be intentional (e.g., not taking medications because of side effects) or unintentional (e.g., forgetting to take medication). It has 8 items.
The MMAS-8 was originally used in hypertensive patients and the results revealed that it was a reliable tool (α = 0.83) and had a significant correlation with blood pressure control. It showed a sensitivity of 93% in detecting patients with poor blood pressure control. 29 We used the Persian version of MMAS-8 validated by Moharamzad et al. 30 for hypertensive patients in Iran. They showed its acceptable internal consistency (α = 0.697), and good test−retest reliability (r = 0.94). Total score ranges from 0 to 8, where a score of 8 shows high adherence, a score of 6−7 indicates moderate adherence, and a score <6 shows low adherence.
After obtaining ethical approval from the university and obtaining informed consent from the participants, questionnaires were distributed among them in the clinic by the last author. After their completion, their data were analyzed in SPSS v.22 software using descriptive statistics (mean, standard deviation, frequency, percentage), Pearson's correlation test (to examine the relationship between the scores of MMAS and BIPQ-R), independent t-test (to examine the difference in MMAS-8 and BIPQ-R scores of patients in terms of age, gender, and place of residence), one-way ANOVA (to examine the difference in MMAS-8 and BIPQ-R scores of patients in terms of marital status, occupation, and education), and multiple regression analysis (to find the predictors of treatment adherence).
The results of Kolmogorov−Smirnov test showed that the data had normal distribution for both study variables (p > 0.05). The significance level was set at 0.05.
Based on the answers to the questions in BIPQ-R, most of patients perceived that: the illness had "moderately" affected their life (rated 5 out of 10; n = 61, 23%); their illness would continue "for a while" (rated 4 out of 10; n = 43, 16.2%); they had a "moderate" amount of control over their illness (rated 6 out of 10; n = 45, 17%); treatment was "moderately" helpful for them (rated 5 out of 10; n = 62, 23.4%); they experienced some symptoms from their illness  Table 2). Table 3 Table 3 showed a significant difference in terms of education (p < 0.001) and occupation (p = 0.010) where those with university education and those who were employed had higher mean scores (p < 0.05). No significant difference was found in terms of marital status (p = 0.327). Table 4  terms of gender (p = 0.357) and age (p = 0.376). Moreover, results of one-way ANOVA presented in Table 4 showed a significant difference in terms of education (p = 0.045), where those with university education had higher adherence compared to other education groups (p < 0.05). No significant difference was found in terms of marital status (p = 0.260) and occupation (p = 0.719).

ACKNOWLEDGMENTS
This study was extracted from the professional doctorate thesis of the last author. The authors would like to thank all the patients participated in the study.

CONFLICT OF INTEREST STATEMENT
The authors declare no conflict of interest.

DATA AVAILABILITY STATEMENT
The data sets used and analyzed during the current study are available from the corresponding author on reasonable request.

ETHICS STATEMENT
All procedures performed in this study were in accordance with the Informed consent was obtained from all individual participants included in the study.

TRANSPARENCY STATEMENT
The lead author Farideh Malekshahi affirms that this manuscript is an honest, accurate, and transparent account of the study being reported; that no important aspects of the study have been omitted; and that any discrepancies from the study as planned (and, if relevant, registered) have been explained.